Condensation removal for use with a draft inducer

ABSTRACT

A condensation removal apparatus is disclosed. The condensation removal apparatus is used with a hot water heater wherein the hot water heater produces a fuel exhaust. The fuel exhaust from the hot water heater is provided to a draft inducer through an inlet which includes a thermally conductive plate having a hole through which the fuel exhaust flows. The draft inducer mixes ambient air with the fuel exhaust and reduces the temperature of the mixture as compared to the fuel exhaust. The mixture is directed to an outlet of the draft inducer and through piping into another environment. As the mixture cools, condensation forms within the piping. The condensation drips back down through the draft inducer. The condensation is then directed onto the thermally conductive plate. Since the thermally conductive plate maintains a high temperature, the condensation is turned from a liquid form into a gaseous form and is directed back through the draft inducer to the outlet.

CROSS REFERENCE TO RELATED APPLICATIONS

The Following Application incorporates by reference in its entirety theco-pending U.S. patent application entitled Draft Inducer having aBackwards Curved Impeller having attorney docket number 917/194 andfiled concurrently herewith.

TECHNICAL FIELD AND BACKGROUND ART

The present invention relates to condensation removal and specificallycondensation removal in draft inducers.

Hot water heaters heat water in a tank by burning a fuel source, heatingthe tank, which transfers the thermal energy to the water, and therebyincreases the water's temperature. As the fuel burns, the fuel producesa hot exhaust which is vented away from the hot water heater. In certainhot water heaters draft inducers are used to cool the exhaust. As theexhaust cools, a small amount of the exhaust condenses within either thedraft inducer or the ventilation piping leading from the hot waterheater. This condensation can then flow back into the draft inducer andthe hot water heater. Over long periods of time, the buildup ofcondensation can cause corrosion and thus the deterioration of metalparts within the hot water heater and/or the draft inducer.

Prior art systems have designed special condensation traps to removesuch condensation. This is both costly and also inconvenient. It iscostly in that the manufacturer must design and create the condensationtrap and incorporate the condensation routing into the design. Suchdesigns are inconvenient for the home owner because the condensationwill collect and the collection receptacle must be periodically emptied.

SUMMARY OF THE INVENTION

In a first embodiment of the invention there is provided a condensationremoval apparatus. The condensation removal apparatus is used with a hotwater heater wherein the hot water heater produces an exhaust. When ahot water heater heats hot water, a fuel is ignited and burned. Thisprocess causes the resulting fuel exhaust. The fuel exhaust is ventedfrom the hot water heater through an outlet to a draft inducer. Thedraft inducer has an inlet for receiving the fuel exhaust. The inlet isformed by a hole in a thermally conductive plate. The hole may take theform of any shape. As the fuel exhaust passes through the hole, theplate is heated. The plate's temperature is raised by the exhaust suchthat the plate can turn condensation into a gaseous form. In oneembodiment, the thermally conductive plate is convex in shape. Theconvex shape prevents any condensation that reaches the thermallyconductive plate from reaching the hot water heater. In one embodiment,the hole is at the center of the plate. Any condensation that reachesthe plate is turned into a gaseous state and is forced back out throughthe draft inducer.

The thermally conductive plate is sized to fit within the inlet of thedraft inducer. The draft inducer includes a mixing chamber. Thethermally conductive plate sits between the outlet of the hot waterheater and the mixing chamber. The mixing chamber of the draft inducerincludes one or more openings that allow ambient air to flow into themixing chamber. An impeller situated above the mixing chamber drawsambient air into the mixing chamber, causing a vortex and mixing thefuel exhaust with the ambient air. The fuel exhaust and ambient airmixture is drawn through the impeller and redirected approximatelyninety degrees. In one embodiment, the impeller is a backwards curvedimpeller. The backwards curved impeller is powered by a DC motor whichresides within the impeller housing. As the ambient air mixes with thefuel exhaust the temperature of the mixture is reduced as compared tothe fuel exhaust. The mixture is directed to an outlet of the draftinducer and through piping into another environment. As the mixturecools, condensation forms within the piping. The condensation drips backdown through the draft inducer. The condensation is then directed ontothe thermally conductive plate. Since the thermally conductive platemaintains a high temperature, the condensation is turned from a liquidform into a gaseous form and is directed back through the draft inducerto the outlet.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing features of the invention will be more readily understoodby reference to the following detailed description, taken with referenceto the accompanying drawings, in which:

FIG. 1 is cut-away schematic diagram of a hot water heater;

FIG. 2 shows a cut-away side view of a draft inducer;

FIG. 3 shows an evaporation plate having a convex shape positioned atthe inlet of a mixing chamber; and

FIG. 4 is a flow chart explaining how the evaporation plate is used witha draft inducer.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

Definitions. As used in this description and the accompanying claims,the following terms shall have the meanings indicated, unless thecontext otherwise requires: In the following disclosure the term“exhaust” shall refer to both the fuel exhaust that comes directly fromthe hot water heater, as well as, the ambient air and fuel exhaustmixture unless the context requires a different meaning.

FIG. 1 is schematic diagram of a hot water heater. A hot water heater100 includes a tank 110 having an inlet 112 and an outlet 113. The inlet112 allows unheated water to flow into the tank 110. The outlet 113allows heated water to flow out of the tank 110. The hot water heater100 also includes a fuel source 120 and an ignition device 125 forigniting and burning the fuel source. The water tank 110 along with theignition device 125 and the fuel inlet 126 for the fuel source areencased in a housing 130. The heat from the ignited fuel source 120heats the water tank 110 which thermally transfers its energy to theWater increasing the water's temperature. During the burning of the fuelsource 120, a fuel exhaust is produced. This fuel exhaust is the resultof the byproduct of the burning fuel combined with the thermally warmedair. The fuel exhaust is vented to an outlet 140 which allows the fuelexhaust to flow to an exterior location outside of the housing 130 ofthe hot water heater 100. Since the fuel exhaust is extremely hot,usually in excess of 250 degrees Fahrenheit, the piping 150 that is usedto couple to the outlet of the hot water heater needs to be made out ofa material that can tolerate such temperatures, such as, iron and copperpiping. Standard PVC (polyvinyl chloride) piping has a melting pointwhich is less than that produced by the exhaust from a hot water heater.In order to use PVC piping as the venting material with a hot waterheater, a draft inducer can be employed. The draft inducer allowsambient air to mix with the fuel exhaust causing the exhaust to decreasein temperature prior to the exhaust being vented through the PVC pipingto an outside environment.

FIG. 2 shows a side view of a draft inducer 200. The draft inducer 200has a fuel exhaust inlet 210 which mounts to the hot water heater at thefuel exhaust outlet of the hot water heater from FIG. 1. The exhaustflows into the draft inducer 200 and enters a mixing chamber 220 throughthe fuel exhaust inlet 225. The inlet 225 is a slit or hole in a plate230 that mates with the draft inducer housing 240. In the embodimentthat is shown the plate 230 is circular in shape. Since the exhaust is aheated gas, the gas rises up through the slit 225 and into the mixingchamber 220. The mixing chamber 220 includes one or more openings 250 tothe ambient air. In the present embodiment that is shown, the air inlets250 are equally spaced rectangular cut-outs in the housing 240. Theambient air can flow into the mixing chamber 220 through the openings250 in the housing 240 and mix with the exhaust. The slit 225 at theinlet of the mixing chamber 220 is sized so that only a small portion ofthe fuel exhaust is drawn into the mixing chamber at a given time andmixes with a substantially greater amount of ambient air in order toreduce the temperature of the exhaust. Thus, the ambient air/fuelexhaust mixture will have a lower temperature than that of the fuelexhaust that flows out of the hot water heater. In the process, theinlet plate 230 is heated by the exhaust on the inlet side of the plate.The plate will be heated to temperature that is equal to or in excess ofthe boiling point of water.

An impeller 260 having backwards curved blades 265 spins above themixing chamber, drawing in the ambient air. The impeller 260 creates avortex that mixes the ambient air with the fuel exhaust and draws themixture up into the impeller blades 265. The impeller blades 265 spin ina circular motion and redirect the exhaust mixture approximately 90degrees. The cooled exhaust is then directed by the impeller wheel tothe outlet 270 of the draft inducer and into piping 275. The piping 275carries the exhaust to an outlet 280. For example, the piping mayterminate at the exterior to a home or building. In one embodiment, thepiping may be PVC tubing.

The impeller 260 of the draft inducer that is shown in FIG. 2 is poweredby a DC motor 285. The DC motor 285 resides within the central housingof the impeller structure 290. The blades of the impeller 260 arecoupled to the exterior surface of the impeller structure 290. By usingbackwards curved blades 265 and a DC motor 285, the motor can be of sucha size so as to fit within the impeller structure. FIG. 3 shows theevaporation plate 300. The evaporation plate 300 has a small hole 310through which the fuel exhaust flows through. The plate 300, in generalheats up to between 250 degrees and 300 degrees during the burn cyclewhen water is being heated. In one embodiment, as shown in FIG. 3, theplate 300 is concave in shape, such that the hole through which theexhaust flows is at a higher point than the rest of the plate. Thisshape prevents the plate from allowing any condensation to drip backinto the hot water heater. The evaporation plate 300 preventscondensation build-up, the need for a condensation tank, and the addedpiping that is required for directing the condensation to thecondensation tank.

As the exhaust cools as the result of the draft inducer, a few drops ofcondensation form within the outlet piping. The condensation travels ina downward direction along the interior surface of the outlet piping andinto the draft inducer eventually reaching the impeller section of thedraft inducer. In one embodiment, the housing is formed with channelsinto which the condensation will flow. The condensation continues todrip downward along the interior housing surface of the draft inducerand is directed to the evaporation plate. Since the temperature of theevaporation plate is in excess of the boiling point of water, thecondensation is turned from a liquid form back into a gaseous form andis directed back up through the impeller and to the outlet.

Returning to FIG. 2, the impeller section of the draft inducer isprovided in a curved circular housing 295. The curvature of the housing295 assists in directing the condensation onto the evaporation plate. Itshould be understood by one of ordinary skill in the art that thehousing for the impeller may take any number of shapes without deviatingfrom the intent of the presently described invention.

FIG. 4 is a flow chart showing the methodology for removal ofcondensation using one embodiment of the invention. Unheated water isallowed to enter into an inlet of the hot water heater and fill thewater tank if water is not already present within the tank. The fuel ofthe hot water heater is ignited by an ignition device. The fuel burnsheating the tanking holding the water and creating a fuel exhaust (410).In one embodiment the fuel is gas, in other embodiments the fuel may beoil or another fuel source. The fuel exhaust is vented outside of thehot water heater and is provided to the inlet of a draft inducer. A holewithin a plate at the inlet of the draft inducer allows the fuel exhaustto vent into a mixing chamber (420). The temperature of the plate isincreased by the exhaust to a temperature capable of turning exhaust ina liquid state into a gaseous state. The fuel exhaust is directedthrough the draft inducer (430). The fuel exhaust mixes with ambient airin a mixing chamber and passes through a spinning impeller reducing thetemperature of the exhaust. As the temperature decreases, condensationis formed within the outlet piping from the draft inducer (440). Thecondensation drips back down into the draft inducer due to gravity. Thecondensation which is the fuel exhaust in a liquid state drips onto theevaporation plate (450). The condensation changes from a liquid forminto a gaseous form and is vented to an outside environment.

Although various exemplary embodiments of the invention have beendisclosed, it should be apparent to those skilled in the art thatvarious changes and modifications can be made which will achieve some ofthe advantages of the invention without departing from the true scope ofthe invention. These and other obvious modifications are intended to becovered by the appended claims.

1. A condensation removal apparatus for use with a hot water heaterproducing exhaust, the apparatus comprising: a draft inducer; athermally conductive plate having an exhaust generating side and a draftinducer side, the plate having a hole there through allowing exhaustfrom the hot water heater to pass through the hole from the exhaustgenerating side to the draft inducer side, the exhaust heating thethermally conductive plate to a temperature capable of converting theexhaust in liquid form to a gaseous form, the plate situated between anexhaust outlet of the hot water heater and the draft inducer.
 2. Thecondensation removal apparatus according to claim 1 wherein thethermally conductive plate is convex in shape such that the condensationflows away from the hole.
 3. The condensation removal apparatusaccording to claim 1 wherein the draft inducer has an inlet sized forreceiving the thermally conductive plate.
 4. The condensation removalapparatus according to claim 1 wherein the draft inducer includes amixing chamber for mixing ambient air with exhaust and wherein thethermally conductive plate forms the inlet to the mixing chamber.
 5. Thecondensation removal apparatus according to claim 1, further comprising:a vent inlet in fluid communication with the draft inducer and the hotwater heater.
 6. The condensation removal apparatus according to claim1, further comprising: a vent outlet in fluid communication with thedraft inducer for venting the exhaust to an environment.
 7. Thecondensation removal apparatus according to claim 1, wherein the draftinducer includes a backwards curved impeller.
 8. The condensationremoval apparatus according to claim 7, wherein the draft inducerincludes a motor for rotating the backwards curved impeller, wherein themotor resides within the backwards curved impeller.
 9. The condensationremoval apparatus according to claim 8 wherein the backwards curvedimpeller spins about an axis that is substantially the same as thedirection of gravity.
 10. The condensation removal apparatus accordingto claim 9, wherein the backward curved impeller expels the exhaust at adirection that is substantially perpendicular to the direction that theexhaust enters the backward curved impeller.
 11. The condensationremoval apparatus according to claim 10, wherein the backward curvedimpeller resides in a housing having curved sides allowing condensationto be directed onto the thermally conductive plate.
 12. A method forremoval of condensation resulting from exhaust from a hot water heater,the method comprising: burning a fuel to heat water within the hot waterheater creating a fuel exhaust; venting the fuel exhaust through a holewithin a plate thereby heating the plate to a temperature capable oftransforming fuel exhaust in a liquid state to a gaseous state;directing the fuel exhaust through a draft inducer reducing thetemperature of the fuel exhaust and turning a portion of the fuelexhaust into a liquid state; and evaporating any fuel exhaust in aliquid state when the fuel exhaust in a liquid state drips onto theplate.
 13. The method according to claim 12, wherein in directing thefuel exhaust through the draft inducer includes mixing the fuel exhaustwith ambient air.
 14. The method according to claim 12, furthercomprising: directing the fuel exhaust in a liquid state into troughs onthe interior of the draft inducer toward the plate.